Syringes, autoinjectors, and like injection devices have long been used to deliver medicaments and other substances transdermally. An injection device typically has a reservoir for storing a liquid to be injected, a plunger to pressurize the stored liquid, and an elongated slender pointed needle for penetrating skin and other tissues, so as to deliver the pressurized liquid into the body.
Because the point is very sharp, it easily penetrates human tissues, clothing, protective gear such as rubber gloves, and other articles. This presents a hazard to medical personnel due to unintended pricking of the personnel's body. This can be uncomfortable, can cause the personnel to drop or otherwise mishandle equipment, and most of all, threatens to transfer contaminants from an injected person's blood to the medical personnel.
Countermeasures directed to unintended pricking of the body have been proposed. However, many countermeasures introduce annoying drawbacks. For example, a cover may need to be manually installed and manually removed when needed. This may for example oblige medical personnel to put down other equipment and objects and perform the necessary installation or removal, or otherwise interfere with expeditious performance of medical tasks.
There remains a need for an uncomplicated yet effective protective device for preventing unintended pricking due to exposed needles, or “sharps”, as they have become informally known, which is self-deploying and which makes minimal demands on